Metal-coated cloth and composition and method for making the same



United States Patent METAL-COATED CLOTH AND COMPOSITION AND METHOD FOR MAKING THE SAL HE Charles C. Avery, Jr., Nufley, N. J., assignor to The 'Cravenette Company, Hohoken, N. J., a corporation of New Jersey N0 Drawing. Application October 23, 1956, Serial No. 388,033

17 Claims. (Cl. 117-65) This invention relates to a method of, and composition for, treating flexible web material, including cloth, to render it water repellent and to provide a heat-andlight-reflective metal coating enhancing its heat-insulating properties, and also to the coated product.

Metal-coated flexible web material, including cloth, having enhanced light-and-heat-reflective characteristics has been made by coating the material with flake or powdered metal carried in an adhesive vehicle, the adhesive then being dried or cured. Prior metal-coated cloth, however, when used for certain purposes, e. g., an interlining for garments, has not been altogether satisfactory in that it is often objectionably stiff, thereby undesirably altering the drape or feel of the garment. These prior metal-coated cloths often have not been water" repellent, the cloth, in efiect, having a tendency to leak at the cracks between the small unbroken zones of adhesive into which the adhesive coating layer is broken upon the calendering of the cloth and upon any subsequent sharp flexing thereof. It has been impossible to satisfactorily coat the cloth with a first coating of water-repellent composition and an overcoating of adhesive and powdered metal because of insufficient adherence between the two layers. The same difiiculty has prevented successful coating of the cloth first with an adhesive powdered-metal coating and then with a Water-repellent coating applied thereover.

I have discovered that flexible web materials, particularly initially porous flexible web materials such as cloth, may be rendered persistently water repellent and may at the same time have their heat-insulating properties enhanced by coating with my novel treating composition incorporating as essential-elements thereof water-repellent material and a compatible curable resin adhesive, the mixture being preferably applied to the Web material as the active portion of a water suspension and serving as a vehicle for the cornminuted metal. The coated web material is then heated to a relatively low temperature for suiiicient time to dry the material, cure the resin adhesive, and set the water repellent. After calendering, the cloth has a drape and feel not greatly difierent from that of the uncoated cloth and, when the comminuted metal is selected from one of the light metals, without the addition of a marked amount of weight to the cloth. Coated garment lining material may be used to advantage as linings or interlinings for garments. Heavier weights of cloth treated according to the present invention are useful as tarpaulins and tents, in which use the coated cloth is markedly water repellent, and has substantial heat-insulating properties.

It is among the objects of the invention to provide an improved composition for rendering flexible web materials persistently water repellent and to enhance their light-and-heat-reflective properties.

Further objects of the invention reside in the provision of a method for coating webs of flexible material with such improved composition, and the product produced thereby.

"ice Another object of the invention lies in the provision of a composition of the type indicated which is economical, easily prepared, and readily stored.

A still further object of the invention lies in the provision of a flexible web material such as cloth which is characterized by its marked flexibility and its retention of a high degree of water repellency despite repeated dry cleaning and despite weathering.

Other and further objects of the invention will appear as the description of the composition, method, and product of the invention proceeds.

As above indicated, the composition which serves as a water repellent and an adhesive vehicle for the cornminuted metal consists of a mixture of a water repellent and a compatible heat curable adhesive, such mixture, together with the comminuted metal of the final coating composition, preferably being applied to the flexible web material in the form of a water suspension. The adhesive employed in the presently preferred embodiment of the composition is a heat curable polyamide resin, specifically a copolymer of dilinoleic and trilinoleic acids with ethylene diamine. This resin is preferably incorporated in the aforesaid mixture in the form of a water suspens'oid, a typical suspensoid containing from 42% to 45% resin, by weight.

The preferred heat curable polyamide resin may be prepared in the manner set forth in the Journal of the Chemical Society, February 1948, volume 70, pages 760 to 763. Briefly, in accordance with that method, dilinoleic acid is prepared from castor oil by the preparation of methyl ester which are then distilled to secure a mixture of a predominant amount of methyl dilinoleate and a smaller amount of methyl trilinoleate. The ester is then converted to the acid in the usual manner. The dilinoleic and trilinoleic acids are heated to C., being stirred under vacuum to remove dissolved gases, the material then being subjected to pure nitrogen under pressure.

The calculated amount of ethylene diamine is then added over a period of fifteen minutes at a temperature of 120 C. to C. After addition of the ethylene diamine, the temperature is raised to 200 C. at such a rate that the vapor temperature never exceeds 100 C. The mixture is then held at 200 C. for four hours. During this period, nitrogen is constantly admitted. After the four-hour period, the mixture is held under vacuum at 200 C. with a Dry Ice trap in the vacuum line to catch any amine. The resin is then cooled to C. and poured into containers and stored under inert. gas.

The Water-repellent material employed in the composition of the invention is an inorganic salt Wax emulsion, specifically a zirconium salt wax emulsion buffered to a pH value so as to be compatible with the above polyamide resin. The water repellent incorporates a small amount of a Wetting agent, e. g., an emulsifier, to produce an emulsion of the zirconium salt wax in water. The emulsifying agent must have no rewetting properties.

The following examples of (l) a typical water repellent and metal powder vehicle composition in accordance with the invention, (2) a typical method of forming the final metal powder including treating composition, and (3) a method of treating a cloth with such material are given by way of illustration. It is to be understood that the invention is not to be limited to the specific examples, either as the invention relates to the relative amounts of the ingredients in the composition, as to the method of making such composition, or the method of using such composition in the treating of flexible Web materials, the scope of the invention being defined by the claims appended hereto.

Example 1.Preparatin of water-repellent adhesive vehicle for comminuted metal copolymer of dilinoleic and trilinoleic acids with ethylene diamine in the form of a water suspension thereof. S ecifically, the water suspension of the resin was that designated BlOOlX polyamide suspensoid, made by General Mills, Inc. The resulting mixture was stirred with a fast mechanical agitator and to it was. added the Zirconium salt wax water repellent, the final mixture being well agitated. The resulting material was drawn off into metal drums or wooden barrels and shipped and stored in this manner. The metal powder to be incorporated in the final treating composition was packaged and shipped separately.

Slightly more than 100 gallons of the treating solution isproduced by the addition of 114 lbs. or" B1001X polyamide suspensoid and 80 lbs. of zirconium salt wax emulsion to 74 gallons (592 lbs.) of water. In the present specific example, the ingredients of the water-repellent adhesive vehicle were present in the following percentages by weight:

Percent B1001X polyamide suspensoid 14.5 Zirconium salt wax Water repellent 10.18 Water 75.3

Since the BlOOlX polyamide suspensoid contains from 42% to 45% resin by weight, the above water-repellent adhesive vehicle has approximately the following composition:

Percent Polyamide resin 6.09 to 6.5 Zirconium salt wax 10.18 Water 83.3 to 83.71

The above solution has an optimum pH value of 4.5, but is stable when its pH value lies anywhere between 3 and 5.5. The zirconium salt wax ernuision is, therefore, bnfiered to such value that when added to the polyarnide resin in water in the manner indicated the composition has a pH value lying within the range given above.

Example 2.Preparati0n of waterrepellerzt metalcoating treating composition The above water-repellent adhesive vehicle and the powdered metal as, forexample, flake aluminum, was

shipped to the place where the web material was to be Percent Bl00lX polyamide resin 14.25 Zirconium salt wax water repellent 10.00 Aluminum powder 1.65 Water 74.10

On the basis that from 42% to 45% of the polyamide suspensoid is the solid resin, such resin is present in the composition of Example 2 in the amount of from 5.98% to 6.41% by weight.

Exa'mple 3.Meth0d of treating flexibie web material Rayon cloth, suitable for use as an interlining of a garment, was continuously traversed past a spraying staa 4 tion which applied the composition of Example 2 to the upper side of the cloth. The composition was applied in approximately the amount of 250 cc. to 1 sq. yd. of the cloth. The coated cloth was then dried and cured at from 260 F. to 280 F. (126.7 C. to 137.8" C.) for a period of from three to live minutes to remove the water, to set the water repellent, and to cure'the polyamide resin. After being thus treated,.the coated cloth was calendered in order to break the resin coating into a great number of very small areas so as to restore flexi bility to the coated cloth. 7 V i :x

It is obvious that the compositions set out in Examples 1 and 2 above maybe varied 'to some extent as to the relative amounts of the components therein. Thus, the water-repellent adhesive vehicle of Example 1 functions effectively when the components are varied as follows:

..-Percent I V a a I By-w eight Water suspensoid of copolymer of dilin'oleici and trilinoleic acids with ethylene diamine 13 to 15 Zirconium salt wax emulsion 9 to 11 Water 73 to'76 As stated above, it is obvious that the various ingredients of the treating composition may be varied somewhat within the scope of the invention. Thus, the results of the invention are gained when, in the final coating on the cloth after the expulsion of the water, the coating composition is such that the weights of the polyamide resin, the zirconium salt. wax'emulsion, and the. flake aluminum have ratios on the order of the following: 5.5 to 9 to 1.5., 1

Although in Example 3 the treating composition has been applied to the cloth by spraying, it may also. be applied thereto by other conventional coating methods such as roller coatingor'knife coating. The composi,-

' tion given is free flowing. Its viscosity can be altered by the addition of methyl cellulose as required, the addition of methyl cellulose decreasing the viscosity. of the composition. 7

It has been found that cloth treated in accordance with the invention displays no loss in heat insulation after six dry cleanings. After six dry cleanings, the'water repellency rating of the cloth was found to have dropped 30% and the spray rating to have dropped 2%, these values remaining substantially constant throughout a substantial additional number of dry cleanings. The coating does not affect the wearing quality of the cloth, so that when employed as a lining or interlining the coated cloth will last as long as the cloth before treatment. The coating is markedly weather resistant so that when employed on heavier cloths such as cotton twill and canvas such products are admirably suited for use in the out of doors, as, for instance, tenting, tarp-aulins, and the like. I claim: 1 p

l. A water-repellent composition useful .as a vehicle and binder for the coating of web material with .comminuted metal, said composition comprising: an aqueous dispersion of a mixture of a polyamide resin and a zir-. conium salt wax emulsion.

2. A water-repellent composition useful as -a vehicle and binder for the coating of web material with com} 4. A water-repellent composition useful as'a vehicle and binder for the coating of web material-with comminuted metal, said composition consisting essentially of an aqueous dispersion of a mixture of 6.1% to 6.5% of a copolymer of dilinoleic and trilinoleic acids with ethylene diamine and about of zirconium salt wax emulsion, the percentages being by weight.

5. A water-repellent, metal-coating composition for the treatment of web material, said composition consisting essentially of a water suspension of a mixture of a polyamide resin, a zirconium salt wax emulsion, and flake metal.

6. A water-repellent, metal-coating composition for the treatment of Web material, said composition consisting essentially of a water suspension of a mixture of a polyamide resin, a zirconium salt wax emulsion, and a brightsurfaced flake metal, the weights of the resin, wax, and metal in the composition having a ratio on the order of 5.5 to 9 to 1.5.

7. The water-repellent, metal-coating composition for the treatment of web material, said composition consisting essentially of a water suspension of a mixture of a copolymer of dilinoleic and trilinoleic acid with ethylene diamine, a zirconium salt wax emulsion, and a light, bright-surfaced flake metal.

8. A water-repellent and metal-coating composition for the treatment of web material, said composition consisting essentially of a water suspension of a mixture of a copolymer resin of dilinoleic and trilinoleic acids with ethylene diamine, a zirconium salt wax emulsion, and a light, bright-surfaced flake metal, the composition consisting essentially of from 5.98% to 6.41% resin, from 9% to 11% zirconium salt wax emulsion, from 1.5% to 1.75% flake aluminum, all percentages by weight, and water.

9. Flexible web material coated with a mixture of a polyamide resin, a zirconium salt wax emulsion, and flake metal, the polyamide resin being cured and bonded to the material.

10. Initially porous web material coated with a mixture of a polyamide resin, a zirconium salt wax emulsion, and a bright-surfaced flake metal, the polyamide resin being cured and bonded to the material and the weights of the resin, emulsion, and metal in the coating having a ratio on the order of 5.5 to 9 to 1.5.

11. Cloth coated with a mixture of a copolymer resin of dilinoleic and trilinoleic acids with ethylene diamine, zirconium salt wax emulsion, and a light, bright-surfaced flake metal, the polyamide resin being cured and bonded to the cloth, the coating when applied consisting essentially of from 5.98% to 6.41% resin, from 9% to 11% emulsion, from 1.5% to 1.75% metal, and water, all by weight.

12. Cloth coated with a mixture of a copolymer resin of dilinoleic and trilinoleic acids with ethylene diamine, zirconium salt wax emulsion, and comminuted aluminum, the resin being cured and bonded to the cloth, the solids in the coating upon application having a composition of approximately 34% resin, 57% emulsion, and 9% aluminum, all by weight, the cured coating having a weight per square yard on the order of .009 pound.

13. Cloth coated with a mixture of a copolymer resin of dilinoleic and trilinoleic acids with ethylene diamine, zirconium salt wax emulsion, and comminuted aluminum, the resin being cured and bonded to the web, the coating resulting from the deposition on the cloth and the curing of a coating composition composed of approximately 6% resin, 10% zirconium salt wax emulsion, 1.65% aluminum powder, and water, all percentages being by weight.

14. The method of rendering a web material water repellent and enhancing its heat-insulating properties which comprises coating the Web material with a composition, the active portion of which is composed essentially of a mixture of a polyamide resin, a zirconium salt wax emulsion, and a comminuted, bright-surfaced metal, and then curing the resin.

15. The method of rendering a web material water repellent and enhancing its heat-insulating properties which comprises coating the web material'with a composition consisting essentially of a water suspension of a mixture of a polyamide resin, a zirconium salt wax emulsion, and a comminuted, bright-surfaced metal, and then drying the coating and curing the resin, the weights of the resin, emulsion, and metal in the composition having a ratio on the order of 5.5 to 9 to 1.5

16. The method of rendering a porous web material water repellent and enhancing its heat-insulating properties which comprises coating the porous web material with a composition consisting essentially of a water suspension of a copolymer resin of dilinoleic and trilinoleic acids with ethylene diamine, zirconium salt wax emulsion, and a light, bright-surfaced comminuted metal, then drying the material and curing the resin, and then calendering the coated web material.

17. The method of rendering cloth water repellent and enhancing its heat-insulating properties which comprises coating the cloth with a composition consisting essentially of a water suspension of a copolymer resin of dilinoleic and trilinoleic acids with ethylene diamine, zirconium salt wax emulsion, and comminuted aluminum, the composition being composed of from 5.98% to 6.41% resin, from 9% to 11% emulsion, from 1.5% to 1.75% aluminum, all by weight, and Water, then drying the cloth and curing the resin by heating the coated cloth at 260 F. to 280 F. for a period of from three to five minutes, and then calendering the dried coated cloth.

References Cited in the file of this patent UNITED STATES PATENTS 1,210,375 Decker Dec. 26, 1916 1,673,797 Brown June 19, 1928 1,765,676 Jones June 24, 1930 1,877,394 George Sept. 13, 1932 2,191,362 Widmer Feb. 20, 1940 2,191,556 Carothers Feb. 27, 1940 2,518,148 Jordan et al. Aug. 8, 1950 2,641,558 Urban et al. June 9, 1953 FOREIGN PATENTS 223,529 Great Britain Nov. 13, 1924 

15. THE METHOD OF RENDERING A WEB MATERIAL WATER REPELLENT AND ENHANCING ITS HEAT-INSULATING PROPERTIES WHICH COMPRISES COATING THE WEB MATERIAL WITH A COMPOSITION CONSISTING ESSENTIALLY OF A WATER SUSPENSION OF A MIXTURE OF A POLYAMIDE RESIN, A ZIRCONIUM SALT WAX EMULSION, AND A COMMINUTED, BRIGHT-SURFACED METAL, AND THEN DRYING THE COATING AND CURING THE RESIN, THE WEIGHTS OF THE RESIN, EMULSION, AND METAL IN THE COMPOSITION HAVING A RATION ON THE ORDER OF 5.5 TO 9 TO 1.5. 